Steam-boiler



(No Model.)

.l D. F. GOGHLAN & T. H. SEARS.

STEAM BOILEB.. NG. 350,912. y Patented Oct. 19, 1886..

N PETERS. PlmxmLiumgmphr. wnshmgwn. D. C.

UNITED STATES PATENT Ormea.

DAVID F. COGHLAN AND THOMAS H. SEARS, OF HOLYOKE, MASSACHUSETTS.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 350,912, dated October 19, 1886.

Application filed October 3, 1885. Serial No. 178,897. (No model.)

To all whom it may concern:

Be it known that we, DAVID F. COGHLAN and THOMAS H. SEARS, citizens of the United States, residing at Holyoke, inthe county of Hampden and State of Massachusetts, have invented certain new and useful Improvements in Steam-Boilers, of which the following` is a specification, reference being had to the accompanying drawings, forming a part thereof.

Our invention relates to improvements in Water-tube steamboilers, or combined cylindrical and water tube boilers; and the objects of our improvements are, first, to increase the heating-surface; second, to bring the products of combustion more directly and continuously in contact with the heating-surface; third, to bring the water into more direct contact with the heatingsurface, fourth, to produce a better circulation of the water, and, fifth, to prevent the deposit of sediment in the tubes. Wey attain these objects by the mechanism illustrated in the accompanying drawings, in Which- I Figure l is a front elevation of the boiler; Fig. 2, a sectional side elevation; Fig. 3, a rear elevation of a portion thereof, and Fig. 4 an enlarged view of certain parts shown in Fig. 2.

Similarletters refer to like parts throughout the several views.

A is a cylindrical boiler,with the water-legs B and C supporting it upon a suitable setting. B and C communicate with the space in the cylinder, as shown, and are also connected with each other by a series of tubes, D D, Src. Passing through said tubes D D, &c., respectively, are the tubes EE, &c., which extend entirely through the water-legs B and C. By this arrangement there is an annular space for water within the tubes D and surrounding the tubes E. There is also a iire-space Within the tubes E and around the tubes D, thus forming a central-fire-tube water-tube boiler. Below the tubes and at front end is an ash-pit, F, grate G, and combustion-chamber H. The bridge-wall K at the back of the combustionchamber is carried up to the tubes, and above it is a bridge-plate, L, of suitable material. The bridge-plate L extends the entire Width of the combustion-chamber and to the height of the top of the tubes. The plate L has suitable holes for the tubes D to pass through, but tits with suiiicient closeness to prevent the direct passage of the liame over the bridge-wall, thus causing it to pass upward around the tubes to the top of the plate, there striking the boilershell A, and the furnace being surrounded by suitable masonry, (not shown in the drawings) the flame then passes downv around the tubes beyond the bridge-wall into the rear end of the central fire-tubes, E E, Ste., and thence out at the front end of said tubes into a suitable uptake or smoke-Hue. The arrangement described effectually secures the object of bringing the products of combustion into direct and continuous contact with the heating-surface. Large heating-surface is secured and the water brought into close contact with it by the two sets of tubes described. The water fills a space in the form of a thin cylinder heated Without and within. To improve the circulation and prevent thedeposit of sediment, the tubes are placed in an inclined position, as shown, rather than horizontal. By the use of the central tire-tube there is a narrowing of the space from a cylinder to a cylindrical shell in the water-tube, thus increasing the force of the current and sweeping all sedimentout.

The form of the rear water-leg, C, is shown in Fig. 3. A foot, c, upon each side, forming a part of the water-space, serves as a support and leaves a central passage for the iiame and gases. The front end, B, is of similar construction. The water in the boiler entirely fills the water-tube space and partially fills the Cylindrical boiler A above, leaving the necessary steam-space. Suitable openings or nozzles for steam-outlet are provided at a c, and a manhole at b.

The arrangement of the central fire-tubes, E, and water-tubes D is shown on a larger scale in Fig. 4.

Having fully described our invention, what We desire to claim and secure by Letters Patent is- In a steam-boiler, the combination,with the cylindrical boiler or drum A, provided with front and rear water-legs, B and C, communicating therewith, the rear leg, C, having feet c,which communicate with said legs', between A products of combustion upward, substantially which is a central passage for the products of as set forth.

combustion, of lthe inclined tubes D, opening DAVID F. COGHLAN.

into said Water-legs, the inclined tubes E, ar- THOMAS H. SEARS.l 5 ranged centrally in the said tubes D, and pass- Witnesses:

ing entirely through the said water-legs, and GAB. MARCHAND,

the central bridge-plate, L, for diverting the H. K. HAWES. 

